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 A121360 Smallest k such that A002217(k)=n. 1
 2, 1, 8, 14, 26, 62, 134, 393, 1257, 4659, 9314, 27933, 167073, 334142, 4677862, 14033577, 56134292, 2133102298, 11788191218, 52541651594 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Least number which becomes prime or 0 or 4 after n-1 iterations of f(x) = sum of prime factors of x (cf. A001414). Agrees with A048133 except for the second term. a(21) <= 536226160966. a(22) <= 2681130804805. a(23) <= 8512643845707. - Donovan Johnson LINKS CROSSREFS Cf. A002217, A001414, A048133. Sequence in context: A102735 A088960 A263528 * A199928 A047688 A089925 Adjacent sequences:  A121357 A121358 A121359 * A121361 A121362 A121363 KEYWORD nonn AUTHOR Klaus Brockhaus, Jul 27 2006 EXTENSIONS Edited comment and a(19)-a(20) from Donovan Johnson, Oct 16 2010 STATUS approved

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Last modified December 17 00:41 EST 2018. Contains 318191 sequences. (Running on oeis4.)